Human dental pulp stem cells (DPSCs) are multi-potent mesenchymal stem cells that have several differentiation potentials. An understanding of the tissues that differentiate from these cells can provide insights for future regenerative therapeutics and tissue engineering strategies. The mesiodens is the most frequent form of supernumerary tooth from which DPSCs can differentiate into several lineages similar to cells from normal deciduous teeth. Recently, it has been shown that nanoscale structures can affect stem cell differentiation. In our presentstudy, we investigated the effects of a 250-nm nanoscale ridge/groove pattern array on the osteogenic and adipogenic differentiation of dental pulp cells from mesiodenscontaining human DPSCs. To this end, the expression of lineage specific markers after differentiation induction was analyzed by lineage specific staining and RT-PCR. The nanoscale pattern arrayed surface showed apositive effect on the adipogenic differentiation of DPSCs. There was no difference between nanoscale pattern arrayed surface and conventional surface groups onosteogenic differentiation. In conclusion, the nanoscale ridge/groove pattern arrayed surface can be used to enhance the adipogenic differentiation of DPSCs derived from mesiodens. This finding provides an improved understanding of the effects of topography on cell differentiation as well as the potential use of supernumerary tooth in regenerative dental medicine.
Cell Differentiation ; Dental Pulp ; Humans* ; Mesenchymal Stromal Cells ; Stem Cells ; Tissue Engineering ; Tooth, Deciduous ; Tooth, Supernumerary*

Skin-derived precursors (SKPs) have potential to differentiate to various cell types including osteoblasts, adipocytes and neurons. SKPs are a candidate for cell-based therapy since they are easily accessible and have multipotency. Most mammalian cells are exposed to a low oxygen environment with 1 to 5% O2 concentration in vivo, while 21% O2 concentration is common in in vitro culture. The difference between in vitro and in vivo O2 concentration may affect to the behavior of cultured cells. In this report, we investigated the effect of hypoxic condition on stemness and proliferation of SKPs. The results indicated that SKPs exposed to hypoxic condition for 5 days showed no change in proliferation. In terms of mRNA expression, hypoxia maintained expression of stemness markers; whereas, oncogenes, such as Klf4 and c-Myc, were downregulated, and the expression of Nestin, related to cancer migration, was also downregulated. Thus, SKPs cultured in hypoxia may reduce the risk of cancer in SKP cell-based therapy.
Adipocytes ; Anoxia ; Cells, Cultured ; In Vitro Techniques ; Nestin ; Neurons ; Oncogenes ; Osteoblasts ; Oxygen ; RNA, Messenger

Transfection is a gene delivery tool that is a popular means of manipulating cellular properties, such as induced pluripotent stem cell (iPSC) generation by reprogramming factors (Yamanaka factors). However, the efficiency of transfection needs to be improved. In the present study, three transfection protocols - non-liposomal transfection (NLT), magnetofection and electroporation - were compared by analysis of their transfection efficiencies and cell viabilities using human dental pulp cells (hDPC) and bovine fetal fibroblasts (bFF) as cell sources. Enhanced green fluorescent protein gene was used as the delivery indicator. For magnetofection, Polymag reagent was administrated. NLT, FuGENE-HD and X-treme GENE 9 DNA transfection reagents were used for NLT. For electroporation, the Neon(TM) and NEPA21(TM) electroporators were tested. Neon(TM) electroporation showed highest transfection efficiency when compared with NLT, magnetofection, and NEPA21(TM) electroporation, with transfection efficiency of about 33% in hDPC and 50% in bFF, based on viable cell population in each cell type. These results suggest that transfection by Neon(TM) electroporation can be used to deliver foreign genes efficiently in human and bovine somatic cells.
Cell Survival ; Cells, Cultured* ; Dental Pulp ; DNA ; Electroporation ; Fibroblasts ; Genes, vif ; Humans ; Indicators and Reagents ; Pluripotent Stem Cells ; Transfection*

OBJECTIVES: This study investigated the prescribing patterns of atypical antipsychotics for the various psychiatric disorders in the psychiatric ward of a University hospital. METHODS: We reviewed the medical records of patients who were discharged from an open psychiatric ward from May, 2003 through April, 2014. The association between psychiatric disorders and prescription pattern of atypical antipsychotics was analyzed. RESULTS: The study included 3091 patients' prescription of psychiatric medication. 60% of prescription included antipsychotics; quetiapine was the most frequently prescribed antipsychotics, but the average dosage was the lowest among all the atypical antipsychotics. According to the diagnoses, prescription rates and dosage of antipsychotics were different. Prescription rates of antipsychotics were the lowest in patients with anxiety disorders, and the mean dosage were the lowest in those with delirium, dementia, and amnestic and other cognitive disorders. CONCLUSION: This observational study shows prescription patterns of atypical antipsychotics for the treatment of psychiatric disorders in a University hospital; atypical antipsychotics were widely used for the treatment of the various disorders, and there were differences in prescription patterns for each disorders. The results of this study may be used to identify the proper atypical antipsychotics effective on certain psychiatric disorders and to propose expanding the indications of each atypical antipsychotics in the future.
Antipsychotic Agents* ; Anxiety Disorders ; Delirium ; Dementia ; Diagnosis ; Humans ; Medical Records ; Observational Study* ; Prescriptions* ; Quetiapine Fumarate

PURPOSE: The purpose of this study was to examine whether non-cognitive student attributes such as learning style and personality type affected academic performance in a flipped learning classroom of a pre-dental undergraduate science course. METHODS: ‘Biodiversity and Global Environment,’ a 15-week, 3-credit course, was designed as a flipped class in Seoul National University School of Dentistry in 2017. Second-year pre-dental students were required to enroll in the course and to engage in online learning and in-class discussion. The Kolb's Learning Style Inventory and the Myers-Briggs Type Indicator were conducted to measure non-cognitive student factors. Independent samples t-test and multivariate regression analyses were used to examine the relationships between self-rated measurements and academic achievement. RESULTS: More than half of the students enrolled in the flipped science course had an assimilator learning style (50%), followed by convergers (24%), accommodators (16%), and divergers (10%), and their personality types were dominated by the introverted, sensing, thinking, and judging types, respectively. Examining group differences using the t-test demonstrated a significant relationship between the diverger group and higher academic success. In particular, the multivariate regression analysis indicated that both thinking types and female students performed better in discussion than feeling types and male students. CONCLUSION: To operate the flipped learning classroom more effectively in medical and dental education, the instructor should carefully develop and apply a more tailored facilitation and relevant assessment by considering student learning styles and personality types.
Dentistry ; Education, Dental ; Female ; Humans ; Learning* ; Male ; Personality Inventory ; Seoul ; Thinking

OBJECTIVES: Six cases of tardy ulnar neuropathy caused by cubitus varus deformity are presented. Clinical features and electrodiagnostic study of six cases were analysed to understand the mechanim of nerve palsy and the usefulness of electrodiagnostic study. METHODS: Electrodiagnostic study and elbow flexion test were performed and elbow varus angle, internal rotation angle of shoulder, biceps and brachioradialis muscle activities were measured in 6 patients RESULTS: Decreased ulnar nerve motor conduction velocities in the elbow segment was shown in 5 patients. Prolonged distal latency and reduced amplitude of ulnar sensory nerve action potentials were shown in one patient. Needle electromyography showed large amplitude motor unit action potentials in ulnar innervated forearm or hand muscles. The mean values of varus angle and internal rotation angle of humerus were 21degrees, and 28degrees, respectively. Brachioradialis showed relatively higher activity than biceps brachii in the early phase of elbow flexion. Three patients underwent surgery and showed immediate symptom relief. CONCLUSION: Tardy ulnar nerve palsy in cubitus varus thought to be caused by internal rotation of distal segment of humerus, stretching of ulnar nerve, snapping of the medial head of triceps on ulnar nerve and anterior transposition and compression of ulnar nerve. The three dimensional corrective osteotomy could be the most efficient treatment to restore the anatomic alignment of the elbow joint.
Action Potentials ; Congenital Abnormalities* ; Elbow ; Elbow Joint ; Electromyography ; Forearm ; Hand ; Head ; Humans ; Humerus ; Muscles ; Needles ; Osteotomy ; Paralysis ; Shoulder ; Ulnar Nerve* ; Ulnar Neuropathies*

The purpose of this study is to evaluate changes of occlusion following the placement of preformed metal crown in the permanent first molar affected by severe caries or hypomineralization.
The study was conducted on 24 patients who met the criteria among the patients with occlusion in the permanent first molar reaching the occlusal plane. Restorative treatment was performed on one first molar using preformed metal crown. Before treatment, immediately after treatment, after 4 weeks, and after 8 weeks, the T-scan Ⅲ was used for measuring distribution of bite force at the maximum intercuspal position, and overbite was measured with digital vernier calipers and change of dental midline was surveyed. After 8 weeks, questionnaires survey was conducted.
In most cases, immediately after treatment, the distribution of bite force between the restored side and non-restored side of arch was reversed compared to before treatment, and the overbite was decreased. However, after 4 weeks, bite force of the left and right side was balanced and the distribution of bite force on the restored and non-restored permanent first molars had similar values. Also, the changed overbite and midline were returned to pre-treatment status and there was no significant temporomandibular joint and masticatory discomfort after treatment.
In this study, it was confirmed that spontaneous occlusal equilibrium was achieved one month after the placement of preformed metal crown.

BACKGROUND: The epidermal growth factor receptor (EGFR) is known to be involved in many tumor promoting activities. EGFR inhibition has been tried as a therapeutic modality in many human malignancies. METHODS: The expression of EGFR protein and the gene copy number changes were studied in 135 clear cell carcinomas and 16 papillary renal cell carcinomas (RCCs), and these tumors were diagnosed between 1995 and 1997. RESULTS: An EGFR protein expression (2+ and 3+) was found in 54.1% of the clear cell RCCs and in 43.8% of the papillary RCCs. In the clear cell RCCs, its expression was associated with male gender, the tumor size (> or =4 cm) and high T stages (T2 and T3), with statistical significance. Trisomy and polysomy of the EGFR gene were found in 27 (25.7%) and 40 (38.1%) of 105 clear cell RCCs, respectively. Trisomy and polysomy were correlated with an EGFR protein expression and a high clinical T stage, with statistical significance. Among 15 papillary RCCs, 13 tumors showed trisomy (86.7%) and one showed polysomy (6.7%). Amplification was not found in both the clear cell and papillary type RCCs. CONCLUSIONS: A considerable numbers of RCCs showed an overexpression of EGFR protein and increased EGFR gene copy numbers, yet the clinical significance of conducting a FISH study in RCC patients seems to be limited.
Carcinoma, Renal Cell ; Coat Protein Complex I ; Gene Dosage ; Genes, erbB-1 ; Humans ; Male ; Ploidies ; Receptor, Epidermal Growth Factor ; Trisomy

Inflammatory pseudotumor is a benign lesion mainly developed in respiratory system. It is difficult to distinguish from malignant lesions, so surgical biopsy is necessary. Of the extrarespiratory system, the inflammatory pseusotumor is rarely developed in the spleen, and first reported by Cotelingam and Jaffe in 1984. We report a case of the inflammatory pseudotumor in the spleen. A 59-years old woman has visited with a splenic mass detected on routine check. She denied the history of abdominal trauma or other diseases except urinary stone and had no subjective symptoms. Tumor markers were all within normal limits. For the differential diagnosis of the splenic mass, splenectomy was done. Grossly, 6x5x4.5 cm sized yellow, hard, well-demarcated mass was seen, and microscopically, prominent fibrosis and collagenation and partial infiltration of plasma cells and neutrophils were found. And the postoperative course was uneventable.
Biopsy ; Collagen ; Diagnosis, Differential ; Female ; Fibrosis ; Granuloma, Plasma Cell* ; Humans ; Middle Aged ; Neutrophils ; Plasma Cells ; Respiratory System ; Spleen* ; Splenectomy ; Biomarkers, Tumor ; Urinary Calculi

While bone marrow (BM)-derived cells have been comprehensively studied for their propitious pre-clinical results, clinical trials have shown controversial outcomes. Unlike previously acknowledged, more recent studies have now confirmed that humoral and paracrine effects are the key mechanisms for tissue regeneration and functional recovery, instead of transdifferentiation of BM-derived cells into cardiovascular tissues. The progression of the understanding of BM-derived cells has further led to exploring efficient methods to isolate and obtain, without mobilization, sufficient number of cell populations that would eventually have a higher therapeutic potential. As such, hematopoietic CD31+ cells, prevalent in both bone marrow and peripheral blood, have been discovered, in recent studies, to have angiogenic and vasculogenic activities and to show strong potential for therapeutic neovascularization in ischemic tissues. This article will discuss recent advancement on BM-derived cell therapy and the implication of newly discovered CD31+ cells.
Bone Marrow ; Regeneration ; Tissue Therapy